Seat upgrades

[Steve McF]

I thought I'd asked this before, but didn't immediately see a thread for it, so apologies if I'm repeating myself.

I have the manual front seats in my Aero. The one thing that bugs me is that you can't seem to tilt the base. Now I'm not sure if you can on the electric seats, but that got me wondering if electric front seats can be retro fitted into a car that didn't have them in the first place.

Would the wiring be there under the carpet, and if it is possible to fit and connect these up, is it then a question of using Tech2 to get them working?

[sgould]

The seats are almost self contained.  The control unit is part of the driver's seat, so it just needs power and switched power.  The switching is done by the I-Bus, so it will need a Tech2 enable.  Not sure if that needs "security access".

[smurkenstein]

My '03 aero had ducting and wires the front driver's seat (but no electric seats) - it was easy to spot.

[aerojon]

manual seats up'n'down back'n'forwards no tilt,yes tilt on the electric seats..

https://www.saabcentral.com/threads/diy-swapping-in-power-memory-seats.242451/

[Steve McF]

Can one get electric but non heated seats too?

Heated seats would mean I need to change the climate control panel?

[sgould]

The electric seats don't have anything to do with the climate control panel.  If you are fitting an electric driver's seat, I think you just need power and an I-Bus wire.  Possibly ignition controlled power as well.

The heated seats pads are just stuck on under the seat cover.  They do need a climate control panel.

[David]

What about converting electric to memory seats? I assume it is simply a matter of swapping over.

[sgould]

I think it would be OK for the drivers seat, but the passenger seat may need the I-bus.  Either way I think the Tech2 will probably be required, maybe not, but I don't know! 

[sgould]

Right!

I've had a look at the seat wiring diagram and there are differences between the electrically adjustable seats and the electric memory seat. 

The electrically adjustable driver's seat has two wires to it, one 12 volt running from the relay in the Rear Electrical Centre (REC) in the boot, and the other is an earth.  It seems that it will work at any time that the switches on the seat are operated.

The passenger electrically operated seat (not memory) is different.  There is a relay in the REC is switched by a command from the I-Bus, which earths the relay.  The logic control of this switching allows the seat to be operated when the ignition is on, and also when the door is open and for 30 seconds thereafter.  The relay is fed by a permanent 12 v feed.

I can't see any reason why the driver's electrically operated (non-memory) seat has no logic control, but the wiring diagram specifically excludes the relay.



The memory seat is different.  The control unit is in the seat and is permanently powered.  It has three wires to it, 12v power, earth, and an I-Bus link.  The I-Bus in the memory seat should prevent the seat from moving unless the ignition is on or the door is open, and for 30 seconds after closing the door.  It also sends the memory info to operate the memory mirrors.

[Steve McF]

So are there two different alternative seats compared to base spec manual ones? Simple electric seats, and memory electric seats?

And the is the REC and wiring under the two front seats likely to be present on a car with manual seats?

[Steve McF]

Anyone got any pictures or diagrams/visuals of what wiring I might expect to see under the front seats? I can buy some electric seats but I want to make sure the car will take them

[sgould]

I had a look at the wiring diagram, and I'm not sure how much help it gives.

All cars have a 40 pin connector under the seat.  But the different functions go via different pins and not all pins will be wired - probably.

But...

If you have an electric driver's seat, the whole lot is connected via pin 37 (12 v power) and pin 38 (earth).
The memory seat uses the same two pins for power, but adds a wire to pin 23 for the I-bus computer data connector.

So it could be a plug-in and see, sort of job.

If you have a manual driver's seat, the same 40 pin connector should be there, but may only be wired for seat heating and airbag.

I've never disconnected the seat connector, but from the picture, it looks as if it could be a Saab modular connector.  This is a frame with inserts.  The inserts may only be present in the frame if the functions they feed are fitted.

[sgould]

Here's a picture of the connector.

[Steve McF]

So if I have the connector under each seat, and pins 37 and 38 are fed by some wiring, we could be in luck to upgrade to electric seats (not too bothered about memory)?

[sgould]

I seems so.  There's no other connection shown that controls the seat.  All the controls, etc. are in the seat.

I've left the other computer now.  But check fuse 25 (? I think ?) in the rear electrical centre in the boot.  It may need to be added even if the wiring is under the seat.